Exercise device



FIG. 1 is a perspective view of an exercise device.

FIG. 2 is a top plan view according to device of FIG. 1; and,

FIG. 3 is a front elevational view according to device of FIG. 1.

The broken lines illustrate portions of the exercise device which form no part of the claimed design. 

The ornamental design for an exercise device, as shown and described. 